The present invention relates to a charged-particle beam exposure apparatus such as an electron beam exposure apparatus or ion beam exposure apparatus mainly used to manufacture a semiconductor integrated circuit, mask, and the like and, more particularly, to a charged-particle beam exposure apparatus for drawing a pattern using a charged-particle beam, and a device manufacturing method using the same.
FIG. 1 is a view showing the schematic arrangement of an electron beam exposure apparatus as an example of a conventional charged-particle beam exposure apparatus. In FIG. 1, reference numeral 710 denotes a work chamber which incorporates an X-Y stage 712 holding a sample 711 such as a semiconductor wafer or a glass mask material. The X-Y stage 712 is driven by an X-Y stage controller 713 in the X direction (right and left with respect to the sheet surface of FIG. 1) and the Y direction (back and forth with respect to the sheet surface of FIG. 1).
An electron beam optical system 720 is arranged above in the work chamber 710. The optical system 720 is comprised of an electron gun 721, various lenses 722 to 727, a blanking deflector 731, a deflector 732 for changing the beam size, a main deflector 733 for scanning a beam, a sub-deflector 734 for scanning a beam, a beam shaping aperture, and the like. The main deflector 733 positions a beam to a predetermined sub-deflection region (subfield), and the sub-deflector 734 positions a figure drawing position in the subfield. At the same time, the deflector 732 and shaping aperture control the beam shape. While the X-Y stage 712 is continuously moved in one direction, drawing processing is done for a drawing stripe region (region within a range drawable by one continuous movement of the X-Y stage 712). Every time one continuous movement of the X-Y stage 712 ends, the X-Y stage 712 is moved stepwise in a direction perpendicular to the continuous movement direction. This processing is repeated to sequentially perform drawing processing for respective drawing stripe regions.
A main control system 740 outputs drawing control data for each stripe that is stored in a drawing control data memory 741 to a blanking controller 745, beam shaping controller 746, main-deflector controller 747, and sub-deflector controller 748. Each controller controls a control object on the basis of the drawing control data in synchronism with a sync signal from a sync signal generator 749.
More specifically, the main-deflector controller 747 supplies a predetermined deflection signal to the main deflector 733 of the optical system 720 in synchronism with a sync signal from the sync signal generator 749. Then, the electron beam is deflected to scan a designated subfield position. A predetermined time after the main-deflector controller 747 receives the sync signal, the main-deflector controller 747 outputs to the blanking controller 745, beam shaping controller 746, and sub-deflector controller 748 an enable signal representing that the electron beam is settled in the designated position to enable exposure. At the same time, the sub-deflector controller 748 receives a sync signal from the sync signal generator 749, and supplies a predetermined sub-deflection signal to the sub-deflector 734 in synchronism with the sync signal. The beam shaping controller 746 supplies a predetermined deflection signal to the deflector 732 to control the size of the electron beam. The blanking controller 745 supplies a predetermined deflection signal to the blanking deflector 731 to control irradiation of the electron beam. Accordingly, drawing processing is done in units of subfields.
Letting a settling time be a time required for the control object of the control system to reach a target value, the settling time of an electron beam deflected by the main deflector 733 changes depending on the deflection amount. In the prior art, the maximum settling time required to settle an electron beam deflected by the main deflector 733 is regarded as an electron beam settling time in all the deflection amounts, and each controller is controlled using this settling time as a reference (fixed settling time). That is, the fixed settling time after the main-deflector controller 747 receives a sync signal, the main-deflector controller outputs to each controller an exposure enable signal representing that the electron beam is settled in a target position to enable exposure. Depending on the deflection amount of the main deflector 733, a wasteful standby time is set to decrease the productivity of the electron beam exposure apparatus. Further, an actual exposure apparatus comprises a plurality of controllers for controlling deflection of the electron beam for respective subfield exposure processes. In addition, the settling time of an electron beam deflected under the control of each controller changes depending on a preceding state. For this reason, the longest settling time is set as a standby time. As a result, the productivity further decreases.
The present invention has been made in consideration of the above situation, and has as its object to determine a proper settling time for each operation and reduce an unnecessary standby time, thereby obtaining high throughput.
A charged-particle beam exposure apparatus according to the present invention for drawing a pattern on an object to be exposed using a charged-particle beam, comprises a plurality of driving elements for drawing the pattern on the object while scanning the object with the charged-particle beam, a plurality of driving data memories for storing a plurality of time-series driving data strings for driving said plurality of driving elements, each driving data memory sequentially supplying data forming the time-series driving data string from first data to a corresponding driving element in accordance with an operation command, and a pattern memory for storing a plurality of operation command data strings obtained by aligning operation commands and non-operation commands in time-series, the operation commands and the non-operation commands constituting each operation command data string being sequentially supplied from first operation command data to a corresponding driving data memory in accordance with a control signal supplied to the pattern memory. The charged-particle beam exposure apparatus can achieve high throughput.
The plurality of driving elements may include a plurality of types of driving elements, and/or a deflector for deflecting the charged-particle beam, and/or an irradiation controller for controlling irradiation of the charged-particle beam to the object. The irradiation controller controls whether the object is irradiated with the charged-particle beam and/or an irradiation time of the charged-particle beam to the object.
Alternatively, the plurality of driving elements may include a first deflector for deflecting the charged-particle beam and scanning a subfield of the object with the charged-particle beam, and a second deflector for deflecting the charged-particle beam and changing a subfield to be scanned.
Alternatively, the charged-particle beam exposure apparatus may further comprise a charged-particle beam source, and an electrooptic system for projecting on the object the charged-particle beam emitted by the source, and the plurality of driving elements may include a focus correction unit for correcting a focal position of the electrooptic system.
Alternatively, the charged-particle beam exposure apparatus may further comprise a source for generating a charged-particle beam, and an electrooptic system for projecting on the object the charged-particle beam emitted by the source, and the plurality of driving elements may include an astigmatism correction unit for correcting astigmatism of the electrooptic system.
Alternatively, the charged-particle beam exposure apparatus may further comprise a source for generating a charged-particle beam, and an electrooptic system for projecting on the object the charged-particle beam emitted by the source, and the plurality of driving elements may include a deflector for deflecting the charged-particle beam, an irradiation controller for controlling irradiation of the charged-particle beam to the object, and an astigmatism correction unit for correcting astigmatism of the electrooptic system.
Alternatively, the plurality of driving data memories may include an irradiation control data memory for storing a driving data string as irradiation control data for driving the driving elements for controlling irradiation of the charged-particle beam, the irradiation control data memory may include a plurality of unit region data memories for storing irradiation control data necessary for drawing in respective unit regions of the object, and the plurality of operation command data strings stored in the pattern memory may include an operation command data string for sequentially selecting the plurality of unit region data memories.
The charged-particle beam apparatus may further comprise a source for generating a plurality of charged-particle beams, and draw a pattern on the object using the plurality of charged-particle beams.
A device manufacturing method according to the present invention comprises the steps of applying a resist film to a substrate, drawing a pattern on the substrate using a charged-particle beam exposure apparatus, and performing developing processing to the substrate, wherein the charged-particle beam exposure apparatus draws a pattern using a charged-particle beam on the substrate, and includes a plurality of driving elements for drawing the pattern on the substrate while scanning the substrate with the charged-particle beam, a plurality of driving data memories for storing a plurality of time-series driving data strings for driving the plurality of driving elements, each driving data memory sequentially supplying data forming the time-series driving data string from first data to a corresponding driving element in accordance with an operation command, and a pattern memory for storing a plurality of operation command data strings obtained by aligning operation commands and the non-operation commands in time-series, the operation commands and non-operation commands constituting each operation command data string being sequentially supplied from first operation command data to a corresponding driving data memory in accordance with a control signal supplied to the pattern memory. The device manufacturing method can achieve high throughput.
Further objects, features and advantages of the present invention will become apparent from the following detailed description of embodiments of the present invention with reference to the accompanying drawings.